Drop mobility on superhydrophobic surfaces with wettability contrasts

Yutaku Kita, Coinneach MacKenzie-Dover, Alexandros Askounis, Yasuyuki Takata, Khellil Sefiane

Research output: Contribution to journalConference articlepeer-review

Abstract

Numerous attempts to manipulate/transport liquid drops have been conducted over the past ten years to develop functional surfaces for applications such as biochemical microfluidics, self-cleaning, anti-icing and controlled/enhanced heat transfer surfaces. In this paper, we show a millimetre-sized water drop running/jumping, without any external forces, on an interface between two superhydrophobic surfaces with different degrees of wettability. A systematic study of the effect of wettability contrasts on drop motion was carried out employing well-defined micropatterned surfaces with various pillar densities. Motion of the drop precisely deposited by a machine-controlled drop dosing system (KRÜSS DSA100) was captured and analysed using a visual CCD camera and a custom image processing programme. Right after a drop was gently placed on the interface, the drop moved toward the surface with denser pillars i.e. less hydrophobic. Drop motion was instigated by vertical oscillatory motion. In turn, the oscillation was induced by drop surface deformation caused during deposition. Moreover, we found that the drop velocity increased proportionally to the wettability (or pillar density) contrasts between the surfaces.

Original languageEnglish (US)
Pages (from-to)2433-2438
Number of pages6
JournalInternational Heat Transfer Conference
Volume2018-August
DOIs
StatePublished - 2018
Externally publishedYes
Event16th International Heat Transfer Conference, IHTC 2018 - Beijing, China
Duration: Aug 10 2018Aug 15 2018

Bibliographical note

Funding Information:
This work was supported by the Japanese Society for the Promotion of Science (JSPS) KAKENHI Grant Number 17J05137.

Publisher Copyright:
© 2018 International Heat Transfer Conference. All rights reserved.

Keywords

  • Bio and medical applications
  • Condensation
  • Drop motion
  • NEMS/MEMS
  • Superhydrophobic surfaces
  • Two-phase/Multiphase flow
  • Wettability

Fingerprint

Dive into the research topics of 'Drop mobility on superhydrophobic surfaces with wettability contrasts'. Together they form a unique fingerprint.

Cite this